For many years, encodements have been provided on film units and cameras for identification purposes and to convey information about the film unit or camera. The term "encodement" is used herein very broadly to cover a feature of physical media used to communicate one or more bits of information to a machine. "Encodement" is inclusive of alphanumeric text and other indicia. For example, Type 135 (35 mm) film cassettes have a "DX" code on the outside surface of the film canister formed by electrically conductive and non-conductive patches. This film also has optical bar codes, in the form of latent images along longitudinal margins of the filmstrip. Advanced Photo System.TM. film cassettes have magnetic encodements on the film and can have optical encodements identifying print formats. A wide variety of other encodements have been proposed.
A shortcoming is that many of these encodements are permanent once written. For example, electrically conductive patches and latent images do not erase. Other encodements, such as magnetic can be rewritten easily, but reading and writing of the media requires close access to the media. Because of this, such encodements require close access for writing and reading. For example, magnetic encodements require a closely placed magnetic head. Latent images must be photoprocessed. Visible codes must be positioned to be readable and are not easily rewritten, at least for purposes of machine-reading. U.S. Pat. No. 4,806,958 to David Momot and Ensley E. Townsend, discloses a microfilm cassette that has an optical sender and receiver for communicating with similarly configured equipment. The cassette includes a circuit that writes and reads information to electronic memory. The cassette must be registered in a suitable device for reading and writing.
Radio-frequency identification transponders are widely available in a variety of forms. These devices include a non-volatile memory, such as an EEPROM (Electrically Erasable Programmable Read-Only Memory) semiconductor component integrally contained in the transponder. Stored in the non-volatile memory are encoded data. Inlay transponders are identification transponders that have a substantially flat shape. The antenna for an inlay transponder is in the form of a conductive trace deposited on a non-conductive support. The antenna has the shape of a flat coil or the like. Leads for the antenna are also deposited, with non-conductive layers interposed as necessary. Memory and any control functions are provided by a chip mounted on the support and operatively connected through the leads to the antenna. Inlay transponders have been used as layers of identification tags and labels to provide encodements that are accessible at a distance.
It would thus be desirable to provide an improved camera having a radio-frequency identification transponder that can be accessed for writing and reading at a distance.